Field of the Invention
The invention relates to a memory, and particularly relates to a non-volatile memory.
Description of Related Art
When semiconductor enters a deep sub-micron manufacturing process, a device size is gradually decreased, and in view of a memory device, it represents that a size of memory cell becomes smaller and smaller. On the other hand, along with increase of data required to be processed or stored by information electronic products, a memory capacity required in these information electronic products also becomes greater and greater. Regarding the situation that the device size becomes smaller and the memory capacity is required to be increased, to manufacture a memory device with a small size, a high integration degree and good quality becomes a target of effort in the industry.
Since a non-volatile memory device has an advantage that data stored therein is not disappeared after power-off, the non-volatile memory device has been widely used in personal computers and electronic equipment.
A conventional non-volatile memory is composed of a select transistor and a floating gate transistor. Since only one layer of polysilicon is required to be formed, the manufacturing process of such non-volatile memory can be integrated with a manufacturing process of a complementary metal oxide semiconductor transistor, so as to decrease the manufacturing cost.
However, in the conventional non-volatile memory, an input/output (I/O) device is generally adopted to serve as the select transistor, so that the non-volatile memory cannot be operated in a low power and high speed manner.
Moreover, if a core device is adopted to serve as the select transistor in order to achieve the lower power and high speed operation, during a program operation or an erase operation of the non-volatile memory, the select transistor bears an excessive stress, which may cause a problem of oxide breakdown.